Linear vibration actuator having moving coil and moving magnet

ABSTRACT

A vibrating actuator for producing two different vibrations is disclosed, comprising a first moving part including at least three magnets, wherein the magnets are arranged with like polarities facing each other; a second moving part including at least two coils, wherein the coils are wound over the magnets; and a pair of first elastic members affixed to a chassis and to the first moving part; and holding means which are affixed to the second moving part and which furthermore either are affixed to the chassis or form part of the pair of first elastic members. The second moving part forms a tubular structure and the first moving part slides within it to allow free movement. The pair of first elastic members and the holding means are attached to the chassis. Furthermore, a method for manufacturing such a vibrating actuator is disclosed.

FIELD OF THE INVENTION

The present invention is directed to a novel vibrating actuator for avariety of applications, for example, a miniature vibro-tactile actuatorhaving multiple resonant frequencies. More specifically, the novelvibrating actuator provides high-definition haptic output for immersiveexperiences for video, gaming and music and other immersive experiences.

BACKGROUND

The majority of music we traditionally listen to can be regarded ascomplex signals resulting from the addition of several signals, e.g.mixed music signals of multiple instruments or voices. The same is alsotrue for audio signals associated with gaming or video content, wherenot only mixed music signals can be present, but also other complexsignals such as sound effects and additional voices. With thepossibility of electronically recording and reproducing sound, inparticular complex music or audio associated with gaming or videosignals, a further aspect becomes important, namely the conversion ofelectrical signals to sound waves which are perceived by the listenerwhen the sound is reproduced. In order to reduce distortion problemsduring reproduction, U.S. Pat. No. 3,118,022 discloses anelectroacoustic transducer comprising two conductive members, adiaphragm which includes electrets and conductive materials and which issupported between the two conductive members, and a mechanism forelectrically connecting to said diaphragm and the two conductivemembers.

On the other hand, the coupled perception of sound and vibration is awell-known phenomenon. Sound is a mechanical wave that propagatesthrough compressible media such as gas (air-borne sound) or solids(structure-borne sound), wherein the acoustic energy is transported viavibrating molecules and received by the vibrating hair cells in thelistener's cochlea. Vibration, on the other hand, is a mechanicalstimulus which excites small or large parts of the perceiver's bodythrough a contact surface. The coupled perception of sound and vibrationis based on the fact that the human brain receives sound not onlythrough the ears, but also through the skeleton —measurements in aconcert hall or church confirm the existence of whole-body vibrations.The body perception of low frequencies is particularly important for animmersive experience of live music, any music sensation that is desiredto be pleasurable or audio associated with video games, or movies.

Accordingly, high-definition haptic feedback could be used to createimmersive experiences for video, gaming and music and other immersiveexperiences where the vibration is coupled to continuous audible (orvisual) signals. Major requirements for a device to achieve continuoushigh-definition haptic feedback are:

1. large frequency range, ideally from 20 to 1000 Hz, to be able togenerate good quality vibrations over this range, in particular, formusic;

2. heavy moving mass, for effective acceleration;

3. small, especially flat, size to make the device portable or wearable;

4. high power efficiency to enable uninterrupted use;

5. silent vibration to avoid disturbance of the sound experience;

6. steady performance to enable continuous use;

7. cost efficient manufacturing to provide an affordable device.

Vibrotactile voice-coil or moving magnet-type actuators are normallyused in industrial applications and use a voice coil or movingmagnet-type actuator consisting of two parts, one of which is moving andone of which is stationary, wherein the two parts are interconnected byan elastic attachment. The vibration is generated by the interaction ofa movable permanent magnet and a stationary coil surrounding it,wherein, due to the Laplace Force, an alternating current passingthrough the coil interacts with the magnetic field of the magnet andgenerates a mechanical force with changing direction on the magnet—thisresults in a linear movement of the magnet with changing direction,causing the vibration. However, standard linear resonant actuators onlyhave a very narrow frequency range which makes them unsuitable for manyuses including enhanced sound experience.

EP 0 580 117 A2 discloses such a moving magnet-type actuator forindustrial use in control equipment, electronic equipment, machine toolsand the like. In order to improve the performance of the actuator, thestationary part comprises at least three coils and the moving partcomprises at least two permanent magnets arranged with same poles facingeach other such that the magnetic flux is used more effectively becausea highly concentrated magnetic field is created in the plane between themagnets. The elastic attachment interconnecting the magnets and thecoils consists in compression springs. However, the magnetic fieldlines, once they have crossed the surrounding coils, are lost and notguided back to the magnets which results in waste of potential magneticfield. Furthermore, like all industrial vibrators, this actuator isnoisy which makes it unsuitable for many uses including enhanced soundexperience and, in particular, music.

US 2014/0346901 A1 discloses a similar moving magnet-type actuator forindustrial applications also with a moving part comprising permanentmagnets arranged in such a way that the same poles face eachother—however, the elastic attachment does not consist in compressionsprings but in resilient diaphragms, which results in loss of potentialmagnetic field due to the loss of magnetic field lines, and the actuatoris noisy which makes it unsuitable for many uses including enhancedsound experience and, in particular, music, as well.

US 20110266892 discloses a vibration generation device for producingvibration frequencies. The vibration generation device comprises a firstvibrator and a second vibrator. The first vibrator is formed by a pairof magnets and a coil, which are placed in a first elastic supportmembers to produce the first vibration. The second vibrator is capableof freely vibrating in the magnetic field formed by the magnets and themagnetic field generated by the coil. The second vibrator has an otherelastic member for supporting the vibration of the second vibrator.However, the assembly of the first vibrator is contained within thesecond vibrator and the first elastic member operates within theassembly of the other elastic member thereby restricting the vibrationof the first vibrator.

US 20180278137 discloses a vibrating motor with a housing, a stator, avibrator and an elastic support member. The vibrator includes a massblock and magnets. The stator includes a first coil with a first fixingboard and a second coil with a second fixing board. The first and secondcoils are located on opposite sides of the mass block. The linearvibrating motor reduces loss of the magnetic field, which makes it moreefficient, while implementing vibration feedback. However, the linearvibrating motor only operates at one resonant frequency.

WO 2018079251 discloses another type of vibrating motor that requiresless space and provides good responsiveness. The linear vibrating motorincludes a mover with weights, which are affixed on the longitudinal endside of a pair of long magnets. A coil is fixed to a base which has along shape in the longitudinal direction of the pair of magnets. When anelectric current is passed through the coil, it drives and reciprocatesthe mover in the transverse direction to generate vibration. However,the vibrating motor only operates at one resonant frequency.

There is still a need for a vibrating actuator that is efficient atproducing a high definition haptic output for enhanced wide bandfrequency response. Additionally, this vibrating actuator can overcomethe deficiencies of the prior art to create immersive haptic experiencesfor audio associated with video, gaming and music by satisfying therequirements mentioned above.

SUMMARY OF THE INVENTION

A vibrating actuator having two different frequencies of vibration isdisclosed. The vibrating actuator includes a first moving part (210)comprising a frame (310) and one or more magnets (320). In a preferredimplementation of the invention, there are three magnets (320) which arearranged with like polarity facing each other, that is, the north poleof the first magnet faces the north pole of the second magnet and thesouth pole of the second magnet faces the south pole of the thirdmagnet. The vibrating actuator includes a second moving part (220)having one or more coils (410). In the preferred implementation, thereare two coils (412, 414). In an alternate implementation, a compactvibrating actuator comprises only one magnet (320) and one coil (410).The coils (410) are made by winding an enamelled copper wire over abobbin. The coils (410) are wound over the magnets (320). A firstelastic member (230A) and first elastic member (230B), hereincollectively referred to as a pair of first elastic members (230) areaffixed to a chassis (160) at one end, and to the first moving part(210) at the other end. A holding means (240) in the form of a pair ofsecond elastic members, which comprises a second elastic member (240A)and a second elastic member (240B) are affixed to the chassis (160) atone end and to the second moving part (220) at the other end. Theholding means (240) acts as restraining elastic members for the secondmoving part (220). Alternatively, in another variation of thisimplementation, the holding means (240) form a part of the pair of firstelastic members (230). The first moving part (210) produces a firstvibration frequency and the second moving part (220) produces a secondvibration frequency. The first vibration frequency is different than thesecond vibration frequency. The first moving part (210) and the secondmoving part (220) vibrate along the longitudinal axis (X-axis) inopposite directions.

The chassis (160) of the vibrating actuator has a protruding element(162) and a protruding element (164), herein referred to as protrudingelements (162, 164), at diagonally opposite ends along the longitudinalaxis (X-axis). The protruding elements (162, 164) are utilised forattaching the pair of first elastic members (230) and the holding means(240) either by welding or affixing the pair of first elastic members(230) and the holding means (240) with screws.

The chassis (160) has protruding elements (162, 164) which have aprovision for carrying current to the coils (410). The current iscarried by the pair of holding means (240). In another variation, thecurrent is carried by an overlaid conductive path on the pair of holdingmeans (240), which is a flexible printed circuit.

The first moving part (210) comprises the frame (310) and at least threemagnets (320) having equal width (W) in the transversal direction(Y-axis). Furthermore, the two side magnets (322, 326) have equal lengthalong the longitudinal direction (X-axis), whereas the centre magnet(324) is larger in length along the longitudinal direction (X-axis). Inanother variation, the three magnets (322, 324, 326) can have differentlengths. In addition, the width (W) of each magnet (320) can bedifferent. In one variation of the present invention, when more than onemagnet is utilised, the magnets (320) can have a spacer in between themagnets (320). The spacer can be a non-magnetic material. The frame(310) is either a square or a rectangle and is made of stainless steel,brass, nickel, aluminium, copper, plastic, solidified polymer or someother non-ferromagnetic material.

The second moving part (220) includes two coils (412, 414). The coils(412, 414) are wrapped transversally around the frame (310) to form alongitudinal tubular structure to allow free movement of the coils (412,414) over the first moving part (210). The pair of first elastic members(230) and the holding means (240) act like springs to restrain themovement of the first moving part (210) and the second moving part(220). The first vibration frequency is dependent on the mass and theelastic constant of the pair of first elastic members (230). The masscomprises the mass of the magnets and the mass of the frame (310).Likewise, the second vibration frequency is dependent on the mass andthe elastic constant of the holding means (240). The mass comprises themass of a pair of U-shaped structures (420), comprising an U-shapedstructure (420A) and an U-shaped structure (420B) and the mass of thecoils (410).

The coils (410) are attached to each other such that current passes fromone coil (412) to another coil (414) and the two coils (412, 414) arewound in opposite directions. In one variation, the two coils (410) arenot separate but formed as a single coil such that the first half of thecoil is wound in the clockwise direction and the other half of the coilis wound in the anticlockwise direction. Additionally, the pair ofU-shaped structures (420) are also attached to the coils (412, 414). Thepair of U-shaped structures (420) are aligned such that the open facesopposite to the closed faces in the transversal axis (Y-axis) face eachother to form a rectangular tubular structure along the longitudinalaxis (X-axis). In an alternative implementation, the pair of U-shapedstructures (420) can be replaced with a pair of hollow rectangularstructures to form a tubular rectangular structure. The tubularrectangular structure may be fabricated as a right angled trapezoidtubular structure or a right angled trapezoid parallelepiped tubularstructure. The second moving part (220) is formed by the U-shapedstructure (420A) and the attached coil (412); the coil (412) is attachedto coil (414); the coil (414) is attached to the U-shaped structure(420B) such that the open face of the U-shaped structure (420A) and theopen face of the U-shaped structure (420B) are diagonally opposite toeach other. The assembly is connected to form a hollow tubular structurethat slides freely over the frame (310) and the magnets (320) to allowfree movement of the second moving part (220) and the first moving part(210). In a variation of the present implementation, the pair ofU-shaped structures (420) can be closed at the open face. The open facecan be partially or completely closed by using a flat strip of metal ornon-metal or a broad strip of metal to provide structural strength tothe second moving part (220) and to protect the coils (410) from damage.

In one variation, where there is only one coil (410) and one magnet(320), the coil (410) is attached to the U-shaped structures (420) oneach side.

The first elastic member 230A comprises a long strip (606) that connectstwo flat protruding elements (602, 610) by an orthogonal fold, which isrounded. The two flat protruding elements (602, 610) project opposite toeach other along the longitudinal direction (X-axis) and are parallel toeach other. The protruding element (602) is substantially broader alongthe axis orthogonal to the X-Y-plane (Z-axis) than the other protrudingelement (610). The long strip (606) connecting the two protrudingelements (602, 610) has indentations (612), which are symmetrical alongthe centre of the long strip (606) in the transversal direction(Y-axis). The first elastic member (230A) and the first elastic member(230B) are identical to each other. The pair of first elastic members(230) are made of stainless steel and have a Z-like shape. In analternate implementation, the pair of first elastic members (230) can beperforated.

The holding means (240), which in this implementation is the secondelastic member (240A) and the second elastic member (240B) are broaderalong the axis orthogonal to the X-Y-plane (Z-axis) than the pair offirst elastic members (230). Each of the pair of second elastic members(240A, 240B) acts as holding means (240) as described earlier. Forexample, the second elastic member (240A) comprises a long strip (706)that connects two flat protruding elements (702, 710) by an orthogonalfold that is rounded. The two flat protruding elements (702, 710)project opposite to each other along the longitudinal direction (X-axis)and are parallel to each other. The long strip (706) connecting the twoprotruding elements (702, 710) has indentations (712), which aresymmetrical along the centre of the long strip (706) in the transversaldirection (Y-axis). The second elastic member (240A) and the secondelastic member (240B) are identical in shape, size and construction. Thesecond elastic member (240A) and the second elastic member (240B) aremade of stainless steel and have a Z-like shape. In an alternateimplementation, second elastic member (240A) and the second elasticmember (240B) can be perforated.

In another aspect, the vibrating actuator having two differentfrequencies of vibration comprises the first moving part (210) includingthe frame (310) and at least three magnets (320). The three magnets(322, 324, 326) are embedded into the frame (310) and are arranged withlike polarity facing each other, that is, the north poles and the southpoles, resp., facing each other. The second moving part (220) includesone or more coils (410) and at least two U-shaped structures (420). Theone or more coils (410) are wound over the magnets (320) and affixed tothe U-shaped structures (420). The open face of the U-shaped structures(420) can be closed by a metal strip. In an alternate implementation,the U-shaped structures (420) are a rectangular parallelepipedstructure, which can move freely over the frame (310) and the magnets(320). The pair of first elastic members (230) are affixed to thechassis (160) at one end and to the first moving part (210) at the otherend. Further, the holding means (240) are affixed to the chassis (160)at one end and the second moving part (220) at the other end having aconducting wire overlaid on the holding means (240) to energize the atleast one coil (410) for producing vibration. The first moving part(210) and the pair of first elastic members (230) produce a firstvibration frequency. The second moving part (220) and the holding means(240) produce a second vibration frequency. The first vibrationfrequency and the second vibration frequency are different and thevibrations are along the longitudinal axis (X-axis). The conductive wireoverlaid on the holding means (240) is a wire, an enamelled copper wire,an insulated conductor or a flexible printed circuit. In another aspect,the pair of second elastic members (240) acts as a conductive path tocarry current to the coils (410).

In another aspect of the present invention, the mass of the first movingpart (230) and the second moving part (240) determines the resonantfrequencies of the vibrating actuator. Additionally, the elasticconstants of the pair of first elastic members (230) and the holdingmeans (240) determine the resonant frequencies of the vibratingactuator. By appropriately choosing the material for the frame (310),the U-shaped structures (420), the magnets (320), the elasticity of thepair of first elastic members (230) and the holding means (240), the tworesonant frequencies of the vibrating actuator can be designed ordetermined.

In yet another aspect of the invention, the vibrating actuator havingtwo different frequencies of vibration comprises the first moving part(210), the second moving part (220), and a pair of first elastic members(800). The first moving part (210) includes three magnets (320). Thethree magnets (320) are arranged with like polarity facing each other.The second moving part (220) includes one or more coils (410) which arewound over the magnets (320). The pair of first elastic members (800)comprises a first elastic member (800A) and a first elastic member(800B). The first elastic member (800A) and the first elastic member(800B) are formed from a base plate (802), a middle strip (806) and aholding means (830). The holding means (830) comprises outer strips(804A and 804B); the outer strips (804A and 804B) having transversalindentations on the outer faces (812A and 812B), are projectedorthogonally at equal distance from the base plate (802) to terminateinto upper plates (808A and 808B). The upper plates (808A and 808B) areparallel and opposite to the base plate (802). In addition, the upperplates (808A and 808B) are separate and independent of each other. Inaddition, the first elastic member (800A) and the first elastic member(800B) include the middle strip (806), which lies in between the outerstrips (804A and 804B) and extends a small distance from the base plate(802), then is orthogonally projected from the base plate (802).Furthermore, the middle strip (806) terminates into an upper middleplate (810), where the upper middle plate is parallel and projected inthe opposite direction to the base plate (802). The middle strip (806)has transversal indentations along the centre line perpendicular to thebase plate (802). The upper middle plate (810) is separate from theouter strips (804A and 804B). The base plate (802) along with the outerstrip (804A), that terminates into the upper plate (808A), and the baseplate (802) along with the outer strip (804B), which terminates into theupper plate (808B), form two Z-like shapes and act as the holding means(830). In addition, the base plate (802) along with the middle strip(806), which terminates into upper middle plate (810), forms a thirdZ-like shape. The upper plates (808A and 808B) and the middle plate(810) are separated by a small distance to allow free vibration of themiddle plate (810) underneath the upper plates (808A and 808B). Thefirst elastic member (800A) and the first elastic member (800B) areidentical in shape, size and construction. For each elastic member ofthe pair of first elastic members (800), the upper middle plate (810) isattached to the first moving part (210) and the upper plate (808A) andthe upper plate (808B) are attached to the second moving part (220). Thebase plate (802) of the pair of first elastic members (800) is attachedto the chassis (160) through the protruding elements (162, 164).

In another aspect of the invention, the vibrating actuator (100) havingtwo different frequencies of vibration comprises the first moving part(210), the second moving part (220) and a pair of first elastic members(900). The first moving part (210) includes three magnets (320) suchthat the three magnets (322, 324, 326) are arranged with like polarityfacing each other. The second moving part (220) includes one or morecoils (410), which are wound over the magnets (320). The pair of firstelastic members (900) comprises a first elastic member (900A) and afirst elastic member (900B). The first elastic member (900A) and thefirst elastic member (900B) comprise a middle strip (908), a centreplate (904), an upper plate (910) and a holding means (930) projectingfrom upper plate (910). Holding means include two protruding flat strips(906A, 906B), and base plates (902A, 902B) with rounded edges (920). Theupper plate (910) protrudes at least two orthogonal independentprotruding flat strips (906A, 906B) with rounded edges (920); the twoprotruding flat strips (906A, 906B) terminate into base plates (902A,902B) which are parallel to the upper plate (910) and are projected inthe opposite direction with respect to the upper plate (910).Additionally, the middle strip (908) protrudes from the upper plate(910) at an acute angle and terminates into a centre plate (904). Thecentre plate (904) and the upper plate (910) are projected in the samedirection and are parallel to each other. The first elastic member(900A) and the first elastic member (900B) are identical in shape, sizeand construction. For each elastic member of the pair of first elasticmembers (900), the base plates (902A, 902B) are attached to the chassis(160) through the protruding elements (162, 164) and the upper plate(910) is attached to the second moving part (220). The centre plate(904) is attached to the first moving part (210).

In another aspect of the invention, the vibrating actuator (100) havingtwo different frequencies of vibration comprises the first moving part(210), the second moving part (220) and a pair of first elastic members(1000). The first moving part (210) includes three magnets (320) suchthat the three magnets (322, 324, 326) are arranged with like polarityfacing each other. The second moving part (220) includes one or morecoils (410), which are wound over the magnets (320). The pair of firstelastic members (1000) comprises a first elastic member (1000A) and afirst elastic member (1000B). The first elastic member (1000A) and thefirst elastic member (1000B) have a lower base plate (1002B), a firstprojected elastic member (1004), a flat upper plate (1008) and a holdingmeans (1030). The holding means (1030) includes an upper base plate(1002A), which orthogonally protrudes a second projected elastic member(1006) with a rounded edge. The second projected elastic member (1006)terminates, with a rounded edge, into a flat upper plate (1010).

The lower base plate (1002B) is bent orthogonally into a first projectedelastic member (1004), which terminates orthogonally into a flat upperplate (1008) such that the folds have rounded edges. The base plate(1002), comprising upper base plate (1002A) and lower base plate(1002B), is affixed or attached to the chassis (160). The first elasticmember (1000A) is affixed to the first moving part (210) with the upperbase plate (1008). The holding means (1030) is affixed to the secondmoving part (220) with the flat upper plate (1010).

In another aspect of the invention, the vibrating actuator (100) havingtwo different frequencies of vibration comprises the first moving part(210), the second moving part (220) and a pair of first elastic members(1110). The first moving part (210) includes three magnets (320) suchthat the three magnets (322, 324, 326) are arranged with like polarityfacing each other. The second moving part (220) includes one or morecoils (410), which are wound over the magnets (320). The pair of firstelastic members (1110) include a first elastic member (1110A) and afirst elastic member (1110B). The first elastic member (1110A) and thefirst elastic member (1110B) are affixed to the chassis (160) at one endand the other end is affixed to the first moving part (210).Furthermore, the vibrating actuator also includes holding means (1120)in the form of a pair of second elastic members having a second elasticmember (1120A) and a second elastic member (1120B). The second elasticmember (1120A) and the second elastic member (1120B), which act asholding means (1120) are affixed to the chassis (160) at one end and theother end is affixed to the second moving part (220).

In another aspect the present invention, the method of manufacturing avibrating actuator includes assembling a first moving part (210) byassembling at least three magnets (322, 324, 326) in a rectangular frame(310). The magnets (320) face each other with the same polarity.Further, it includes assembling a second moving part (220) by wrappingat least two coils (412, 414) of a self-bonding copper wire around theframe (310) such that the coils (410) formed by the self-bonding copperwire allows free movement of the first moving part (210) inside it. Thecoils (412, 414) are attached to U-shaped structures (420) such thatfirst ends of the coils (410) are attached to each other and second endsof the coils are attached to the U-shaped structures (420), where theU-shaped structures (420) are arranged such that the U-shaped structuresare rotationally symmetrical with respect to the origin at the centre ofthe coils (410). One end of the first elastic member (230A) is attachedto the first moving part (210) and the opposite end of the first elasticmember (230A) is attached to the chassis (160). Likewise, one end of afirst elastic member (230B) is attached to the first moving part (210)and the opposite end of the first elastic member (230B) is attached tothe chassis (160). The holding means (240), is formed by the secondelastic member (240A) and the second elastic member (240B). The secondelastic member (240A) is attached to the second moving part (220) at oneend and the opposite end is attached to the chassis (160). Likewise, thesecond elastic member (240B) is attached to the second moving part (220)at one end and the opposite end is attached to the chassis (160). Themethod of manufacturing of the vibrating actuator further comprisesintroducing a spacer of non-magnetic material between the magnets (320).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an isometric view of the vibrating actuator;

FIG. 2 illustrates an exploded isometric view of the vibrating actuator;

FIG. 3 illustrates a first moving part of the vibrating actuator;

FIG. 4A illustrates a second moving part of the vibrating actuator;

FIG. 4B illustrates the second moving part of the vibrating actuatorwith a strip of metal joining the ends of an U-shaped structure;

FIG. 4C illustrates the second moving part of the vibrating actuatorwith a variation;

FIG. 4D illustrates the second moving part of the vibrating actuatorwith a strip of metal joining the ends of the U-shaped structure in anembodiment of the present invention;

FIG. 5A-5C illustrates the different configurations of the magnets andcoils of the vibrating actuator;

FIG. 5D-5F illustrates the different configurations of the magnets andcoils of the vibrating actuator with spacers;

FIG. 6A-6C illustrates the different views of a first elastic member ofthe vibrating actuator;

FIG. 7A-7C illustrates different views of a holding means having asecond elastic member of the vibrating actuator;

FIG. 7D-7E illustrates the holding means wherein the second elasticmember of the vibrating actuator has an overlaid conductive path;

FIG. 8A-8C illustrates different views of a different type of firstelastic member having a holding means, of the vibrating actuator forconnecting the first moving part and the second moving part to thechassis of the vibrating actuator;

FIG. 8D illustrates an isometric view of the vibrating actuator with apair of the different type of first elastic members;

FIG. 9A-9C illustrates different views of another different type offirst elastic member having a holding means for connecting the firstmoving part to the second moving part and the second moving part to thechassis of the vibrating actuator;

FIG. 9D illustrates an isometric view of the vibrating actuator with apair of another different type of first elastic members;

FIG. 10A-10C illustrates different views of a yet another differentfirst elastic member, having a holding means for connecting the firstmoving part and the second moving part to the chassis of the vibratingactuator;

FIG. 10D illustrates an isometric view of the vibrating actuator with apair of yet another different first elastic members having the holdingmeans for attachment of the second moving part;

FIG. 11A illustrates a pair of a different type of first elastic membersand a pair of a different type of second elastic members of thevibrating actuator;

FIG. 11B illustrates an isometric view of the vibrating actuator withthe pair of a different type of first elastic members and the pair of adifferent type of second elastic members in another variation of theinvention;

FIG. 12A illustrates another means of attaching a pair of a differenttype of first elastic members and a pair of a different type of secondelastic members with the first moving part and the second moving part ofthe vibrating actuator;

FIG. 12B illustrates an isometric view of the vibrating actuator withanother means of attaching the pair of a different type of first elasticmembers and the pair of a different type of second elastic members withthe first moving part and the second moving part;

FIG. 13A and FIG. 13B illustrates the arrangement of the first movingpart and the second moving part of the vibrating actuator;

FIG. 14A is a sectional view along the transversal direction of thevibrating actuator;

FIG. 14B is a sectional view along the longitudinal direction of thevibrating actuator.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to a vibrating actuator for providingwideband haptic feedback, although it can be used in a variety ofapplications that provide vibrotactile feedback. A wide bandwidth inhaptic feedback, for example from 40 to 120 Hz, is important as itreproduces the multiple, complex frequencies found in real worldenvironments. Typically, a moving magnet vibrating actuator or a movingcoil vibrating actuator only has one resonant frequency, for example 110Hz. Such a vibrating actuator can have a useful bandwidth of only 100 to120 Hz. When such a vibrating actuator is utilised to reproduce a rangeof frequencies outside this 100 to 120 Hz range, for example, 60 to 80Hz, it provides a poor user experience due to a strong decrease inefficiency away from the tuned resonant frequency of 110 Hz. Thedecreased efficiency and increased power consumption can degrade theperformance of a device in which the actuator is embedded. For example,the battery life in a mobile device is reduced; the quality of vibrationsignificantly drops in medical applications; the overall performance ofgaming devices such as headsets, gaming consoles, etc, is degraded.There is a need for a technical solution that will spread the useful,efficient bandwidth of an actuator to be able to match the frequencyrange of 40 Hz to 120 Hz, similar to the range of the complexfrequencies found in real world environments.

The above problem with a single frequency vibrating actuator can besolved using a multiple frequency vibrating actuator. In an idealscenario, a single frequency resonant actuator should be capable ofresponding equally to a range of frequencies, however, due to thetypical distribution of the frequency response curve, the vibratingactuator responds efficiently only at the resonant frequency. Otherfrequencies around the resonant frequency are damped out considerably.The problem is solved by having a multiple resonant frequency vibratingactuator that responds efficiently to a wide range of frequencies. Dueto the technical difficulty of incorporating multiple resonantfrequencies in a miniature device, it is advantageous to have at leasttwo resonant frequencies to solve the problem of single resonantfrequency actuators. The novel vibrating actuator responds efficientlyto both the resonant frequencies, say the first resonant frequency f1(60 Hz) and the second resonant frequency f2 (100 Hz). When the tworesonant frequencies are well defined and spread apart to allow a widebandwidth, for example, 60 Hz to 100 Hz, and are still close enough toallow good response in between the two frequencies, then it will allowgood performance across the full wideband frequency range, for exampleevery frequency between 40 and 120 Hz. The innovative vibrating actuatorallows a wide range of frequencies to be efficiently produced withoptimal current consumption; thus enhancing the performance of thevibrating actuator for wideband applications.

The novel vibrating actuator can be utilised in all devices andapplications which provide haptic feedback such as but not limited togaming pads, mobile devices such as mobile phones, tablets, medicalequipment, automotive systems and other application areas. Theinnovative vibrating actuator can also be used to enhance theperformance of all the haptic devices where the performance andcapability of wideband actuators are required, but these devices havebeen constrained by the use of single frequency actuators such as LinearResonant Actuators (LRA) or Eccentric Rotating Mass (ERM) actuators.

The present invention and its advantages are best understood byreferring to the illustrated embodiments shown in the accompanyingdrawings, in which like numbers designate like parts. The presentinvention may, however, be embodied in numerous devices for producinghaptic output and should not be construed as being limited to theexemplary embodiments set forth herein. Exemplary embodiments aredescribed below to illustrate the present invention by referring to thefigures.

In this application, the term “longitudinal” means in the lineardirection of the movement of the moving parts of the vibrating actuator,which is considered along the X-axis; “transversal” means in a directionin the plane orthogonal to the longitudinal direction, which isconsidered along the Y-axis; “orthogonal to X-Y-plane” means in theZ-axis, that is orthogonal to both the X-axis and the Y-axis; and“diagonally opposite” means opposite corners of two parallel sides of asquare or a rectangle structure.

The present invention provides a unique and novel vibrating actuatorhaving two different resonant frequencies. The two different resonantfrequencies are produced by a first moving part and a second moving partwith each of the first moving part and the second moving part suspendedby a pair of elastic members.

FIG. 1 illustrates an isometric view of a vibrating actuator 100 andFIG. 2 shows an exploded view of the vibrating actuator 100. Accordingto the present invention, the vibrating actuator 100 comprises a firstmoving part 210, a second moving part 220, a pair of first elasticmembers 230 (a first elastic member 230A and a first elastic member 230Bcollectively referred to as the pair of first elastic members 230), aholding means 240, which can be in the form of a second elastic member240A and a second elastic member 240B, an outer casing 150, and achassis 160, as shown in FIG. 2 .

The chassis 160 is rectangular in shape but can have other shapes suchas square, parallelogram or other four sided polygon shapes in differentvariations. The chassis 160 has a protruding element 162 and aprotruding element 164 on its longer sides (longitudinal direction) atdiagonally opposite ends. The protruding element 162 and the protrudingelement 164 are rectangular or square in shape and are orthogonal to theX-Y-plane (Z-axis) of the chassis 160, as shown in FIG. 1 . Theprotruding element 162 and the protruding element 164 are utilized foraffixing the pair of first elastic members 230 and the holding means240, which is the second elastic member 240A and the second elasticmember 240B. When the protruding element 162 and the protruding element164 are utilised for affixing the pair of first elastic members 230 andthe holding means 240 with screws, the protruding element 162 and theprotruding element 164 are rectangular blocks with holes. The outercasing 150 and the chassis 160 are preferably made of metal, such asstainless steel, nickel, copper or iron, however, the outer casing 150and the chassis 160 can also be made from plastic or other polymers toreduce the weight of vibrating actuator 100, in other variations. Theprotruding element 162 and the protruding element 164 fit within theouter casing 150, such that outer casing 150 and the chassis 160 allowfree movement of the first moving part 210 inside the second moving part220 and the free movement of the second moving part 220 inside of thechassis 160. In short, the chassis 160 and the outer casing 150 firmlymate with each other to form a long rectangular parallelepiped shapedvibrating actuator 100, which is substantially longer in the horizontal(longitudinal direction) compared to the vertical (transversaldirection) as shown in FIG. 1 .

The first moving part 210 comprises a frame 310 and magnets 320 as shownin FIG. 3 . The second moving part 220 comprises coils 410 and a pair ofU-shaped structures 420. The U-shaped structures 420 comprise a U-shapedstructure 420A and a U-shaped structure 420B as shown in FIG. 4A.

The frame 310 comprises an outer rectangular periphery or an outersquare periphery 302 with a hollow rectangle 304. For illustrating theframe in the present invention, the frame 310 is construed to berectangular, that is, the outer rectangular periphery 302. In thisembodiment, the frame 310 is either a rectangle or a square but othershapes such as a parallelogram, a trapezoid other four sided figure arepossible in other structural configurations. The outer rectangularperiphery 302 edges are rounded, chamfered, or fillet to avoid sharpedges, which can accidentally cause damage to either the first elasticmember 230A or the first elastic member 230B of the pair of firstelastic members 230. For example, an overdrive of the first moving part210 and the second moving part 220 may result in the frame 310accidentally hitting either the first elastic member 230A or firstelastic member 230B. The hollow rectangle 304 in the frame 310 hasrounded corners, which are utilized for placing the magnets 320.Accordingly, the magnets 320 also have rounded edges to mate perfectlywith the frame 310.

The frame 310 is constructed by laser cutting and folding anynon-magnetic sheet metal such as stainless steel, aluminum, nickel,copper, brass, zinc or any other non-magnetic material. In anothervariation, the frame 310 is injection molded out of a polymer such asplastic or can be cast out of any non-magnetic material. When the frame310 is constructed using plastic or any other polymer, the frame 310 canbe printed using a 3D printer for fast assembly.

The long sides of the outer rectangular periphery 302 of the frame 310are along the longitudinal direction (parallel to the long sides of thechassis 160) and have provisions for joining the pair of first elasticmembers 230. A first end of the first elastic member 230A and the firstelastic member 230B are attached on the diagonally opposite long sidesof the outer rectangular periphery 302. The second end of the firstelastic member 230A is affixed to the protruding element 164 of thechassis 160. Likewise, the second end of the first elastic member 230Bis affixed to the protruding element 162 of the chassis 160. The pair offirst elastic members 230 can be affixed to the outer rectangularperiphery 302 by either welding, riveting, gluing, with screws, or viafolds that mechanically mate to form a strong joint or bond.

The magnets 320 are comprised of a series of magnets, such as a firstmagnet 322, a second magnet 324 and a third magnet 326 in the presentinvention, but in other variations more than three magnets can bearranged inside the frame 310. All four edges of the first magnet 322,the second magnet 324, and the third magnet 326 are rounded to avoidsharp edges; although in some variations the sharp edges can also beeliminated by other known geometries. For example, the edges of thefirst magnet 322, the second magnet 324, and the third magnet 326 can bechamfered edges or fillet edges. In another variation, the first magnet322, the second magnet 324, and the third magnet 326 can all havenon-square edges.

The polarities of the first magnet 322 and the second magnet 324 aredisposed to be symmetrical, that is, the north pole of the first magnet322 and the north pole of the second magnet 324 face each other.Likewise, the polarity of the second magnet 324 and the third magnet 326are disposed to be symmetrical, that is, the south pole of the secondmagnet 324 and the south pole of the third magnet 326 face each other.This arrangement of magnets 320 creates a strong magnetic field thatmoves radially outwards from the intersection of the first magnet 322and the second magnet 324 with like poles facing each other (north polefacing north pole) and radially inwards at the intersection of thesecond magnet 324 and the third magnet 326 with like poles facing eachother (south pole facing south pole). Additionally, the first magnet322, the second magnet 324, and the third magnet 326 are equal in width(shown by W in FIG. 3 ) but have different lengths in longitudinaldirection (along the X-axis). For example, in the presentimplementation, the width and length of the first magnet 322 and thethird magnet 326 is equal, while the second magnet 324 has substantiallylarger length. In different variations, the first magnet 322, the secondmagnet 324, and the third magnet 326 can all have equal or unequal widthand length depending upon the frame 310. Additionally, the sizes of themagnets 320 can be the same or different depending upon the requirementsof magnetic field to be generated.

The vibrating actuator has magnets 320, which are arranged with the samepolarity to allow a high concentration of the magnetic field to begenerated inside the coils 410. In this implementation, the highlyconcentrated magnetic field generated in the coils 410 is due to themagnetic fields generated by the first magnet 322, the second magnet324, and the third magnet 326. The highly concentrated magnetic field isdue to the magnets 320, which are arranged such that like poles faceeach other. The binding of the first magnet 322, the second magnet 324,and the third magnet 326 can be very difficult since the like poles ofthe magnets 320 repel each other. The innovative frame 310 is designedto securely hold the magnets 320, for example, the first magnet 322, thesecond magnet 324, and the third magnet 326 in a frame 310. The two opensides of the magnets 320 orthogonal to the X-Y-plane allow closepositioning of the frame 320 with the coils 410, so that maximummagnetic flux passes through the coils 410. Furthermore, the magnets 320can be glued together within the frame 320 to act as a single mass andto secure the magnets 320 inside the frame 310. Furthermore, the frame310 provides additional mass to the first moving part 210. By varyingthe mass of the frame 310 and the magnets 320 different resonantfrequencies and vibration strengths can be achieved.

As discussed earlier, the second moving part 220 comprises the coils 410and the pair of U-shaped structures 420. The coils 410 can be any numberof coils, however, in this embodiment the coils 410 comprise a firstcoil 412 and a second coil 414 as shown in FIG. 4A. The number of coils410 is determined by a simple formula n−1, where n is the number ofmagnets 320, except in a special case when n=1 then there is only onemagnet 320 and one coil 410.

The coils 410 are constructed by winding an enamelled copper wire arounda bobbin, which is long in the transversal direction (Y-axis).Additionally, the length of coils 410 is slightly greater than thelength of the frame 310 to allow free movement of the first moving part210 in the longitudinal direction (X-axis).

In the preferred implementation, there are two coils 410 comprising thefirst coil 412 and the second coil 414 with an equal number of windingsand the same dimensions, however, in other variations as shown in FIG. 5a-5 d there can be different combinations with unequal windings anddimensions of the coils 410. The first coil 412 and the second coil 414are connected together such that the first coil 412 is wound in onedirection, for example, clockwise and the second coil 414 is wound inthe opposite direction, for example, anti-clockwise. In addition, thecentre of the first coil 412 is aligned with the intersection line ofthe first magnet 322 and the second magnet 324 arranged with the northpole facing the north pole of the two magnets 322 and 324. Likewise, thecentre of the second coil 414 is aligned with the intersection of thesecond magnet 324 and the third magnet 326 arranged with the south polefacing the south pole of the two magnets 324 and 326. When analternating electric current passes through the coils 410, thealternating current interacts with the magnetic field of the magnets 320to produce a Lorentz force. The Lorentz force is generated in onedirection during the first half cycle and in the opposite direction inthe second half cycle to produce a vibratory motion in the longitudinaldirection (X-axis). In an alternate implementation, the centre of thefirst coil 412 may not coincide with the line joining the first magnet322 and the second magnet 324 but is near or around it, that is, offcentre and non-coinciding. In another implementation, the centre of thesecond coil 414 may not coincide with the line joining the second magnet324 and the third magnet 326 but is near or around it, that is, offcentre and non-coinciding.

Referring to FIG. 4A-FIG. 4D the different types of U-shaped structuresare shown. FIG. 4A shows the pair of U-shaped structures 420. TheU-shape structure 420A and the U-shaped structure 420B are identical inshape, size, and construction. The U-shaped structure 420A and theU-shaped structure 420B are formed by three different sectionscomprising a T-shaped base plate 424 and two right trapezoid shapedplates 422, that is, a right trapezoid shaped plate 422A and a righttrapezoid shaped plate 422B (the right trapezoid shaped plate 422A andthe right trapezoid shaped plate 422B are collectively referred as theright trapezoid shaped plates 422). The right trapezoid shaped plate422A and the right trapezoid shaped plate 422B have same size anddimensions. In a preferred implementation, the width (W) of the righttrapezoid shaped plates 422A and 422B is slightly greater than or equalto the breadth of the frame 310. The right trapezoid plate 422A has acurved projection 430A and the right trapezoid plate 422B has a curvedprojection 430B. The two curved projections 430A and 430B protrudingfrom the right trapezoid shaped plate 422A and the right trapezoidshaped plate 422B are attached with the T-shaped base plate 424 to formthe U-shaped structure 420A and the U-shaped structure 420B with an openface. The “open face” of the U-shaped structure 420A and the U-shapedstructure 420B herein means the hollow space created between the righttrapezoid shaped plate 422A and the right trapezoid shaped plate 422B,and which is opposite to the T-shaped base plate 424.

The U-shaped structure 420A and the U-shaped structure 420B arefabricated from a non-magnetic sheet metal by cutting and folding it.Alternatively, the U-shaped structure 420A and the U-shaped structure420B can be formed by welding the T-shaped base plate 424 and the righttrapezoid shaped plates 422A and 422B.

The first coil 412 and the second coil 414 are joined together at oneend by a glue or by a bonding material. Alternatively, the first coil412 and the second coil 414 can be integrated into a single coil 410such that half of the coil winding is wound in one direction, that is,clockwise, and the other half of the winding is in the other direction,that is, anti-clockwise. The other end of the coils 412 and 414 isattached with glue or affixed using a bonding material with the U-shapedstructure 420A and the U-shaped structure 420B. The U-shaped structure420A is attached to the coil 412 and the U-shaped structure 420B isattached to coil 414 such that the open faces of the U-shaped structures420 are diagonally opposite each other. As a result, the coil 412, thecoil 414, the U-shaped structure 420A and the U-shaped structure 420Bform a tubular structure respectively along the longitudinal direction(X-axis) to form the second moving part 220, which moves freely over thefirst moving part 210.

Referring to FIG. 4B, the pair of U-shaped structures 420 are depictedwith a small variation. In this implementation, the flat side formed bythe T-shaped base plate 424 and the right trapezoid shaped plates 422Aand 422B of the U-shaped structure 420A and the U-shaped structure 420Bare joined by a metal strip or a rod 440 forming a rectangular frame atone end. The metal strip or the metal rod 440 is made of the samematerial as the pair of U-shaped structures 420. The metal strip or themetal rod 440 provide structural strength and stability for the pair ofU-shaped structures 420. For example, the U-shaped structure 420A has ametal strip or a metal rod 440A at its open face. Likewise, the U-shapedstructure 420B has a metal strip or a metal rod 440B at its open face.In an embodiment, each U-shaped structure of the pair of U-shapedstructures 420 can be transformed into a rectangular or a tubularstructure by joining the entire open face of the right trapezoid shapedplates 422A and 422B.

FIG. 4C shows another variation of the pair of U-shaped structures 420,with each U-shaped structure comprising three different sections: a baseplate 428 having a protruding element 426 orthogonal to the face of thebase plate 428 and two right trapezoid shaped plates 422, that is, afirst right trapezoid shaped plate 422A and a second right trapezoidshaped plate 422B. The first right trapezoid shaped plate 422A and thesecond right trapezoid shaped plate 422B are similar in size anddimensions, and are made of a non-magnetic material. The first righttrapezoid plate 422A and the second right trapezoid plate 422B arejoined to the base plate 428 on either side, such that the entireassembly creates a structure that looks like the U-shaped structure 420Aor the U-shaped structure 420B, as shown in FIG. 4C, with an open face.The U-shaped structures 420 are fabricated by cutting and folding anon-magnetic sheet metal as shown in FIG. 4C. Alternatively, the pair ofU-shaped structures 420 can also be formed by welding the base plate 428to two separate right trapezoid shaped plates 422A and 422B. In thepreferred implementation, the open face of the pair of U-shapedstructures 420 extends slightly beyond the frame 310 in the transversaldirection (Y-axis). The U-shaped structure 420A is attached to coil 412and the U-shaped structure 420B is attached to coil 414 such that theiropen faces are diagonally opposite each other and substantially coverthe longitudinal side (X-axis) of the frame 310 as shown in FIG. 4C. Theprotruding element 426 is used for welding the pair of second elasticmembers 240 with the U-shaped structures 420.

The first coil 412 and the second coil 414 are joined to each other byglue or bonding material. Furthermore, the first coil 412 is attached tothe U-shaped structure 420A by glue or bonding material and the secondcoil 414 is attached to the U-shaped structure 420B such as to form arectangular tubular structure, which moves freely over the first movingpart 210.

Referring to FIG. 4D another variation of fabricating the U-shapedstructures 420 is shown. The U-shaped structure 420B has a metal stripor a metal rod 450B that joins the first right trapezoid shaped plate422A and the second right trapezoid shaped plate 422B, such that themetal strip or the metal rod 450B is parallel to the base plate 428 asshown in FIG. 4D. The U-shaped structure 420A is also fabricated in asimilar manner as the U-shaped structure 420B.

FIG. 5A-5F shows the different arrangements of the magnets 320 and thecoils 410 in different variations of the present invention. All thesevariations can be implemented in the vibration actuator 100 in differentembodiments.

FIG. 5A shows a configuration where two magnets 320 with a single coil410 are provided, with the centre of the coil 410 aligned with theintersection line of the magnets 320.

FIG. 5B shows the preferred implementation with three magnets 320, thatis, the first magnet 322, the second magnet 324, and the third magnet326 and two coils 410, that is, the first coil 412 and the second coil414. In this embodiment, the centres of each of the coils 410 align withthe intersection line between the two adjoining magnets 320. In anothervariation, the intersection line between two adjoining magnets 320 andthe centre of the first coil 412 and the second coil 414 is offset by afew millimeters, for example, between 1 mm to 3 mm.

FIG. 5C shows the arrangement for four magnets 320 and three coils 410.In this arrangement, the coils 410 are separated by a small gap; forexample, the small gap can be between 1 mm and 2 mm. Alternatively, thecoils 410 can be elongated in the X-axis and securely glued to eachother without any gap in between them.

FIG. 5D shows the arrangement of two magnets 320 with a spacer providedin between the magnets 320. The spacer is aligned with a coil 410 suchthat the centre of the coil 410 aligns with the centre of spacer. Thespacer can be a magnetic material or non-magnetic material.

FIG. 5E shows the arrangement of three magnets 320, with spacersprovided in between the magnets 320. The centre of the middle magnet isaligned with the intersection line where the two coils 410 are joined toeach other. Alternatively, the intersection line of the two coils 410can be offset from the centre line of the middle magnet by a fewmillimeters. The spacers can be a magnetic material or non-magneticmaterial.

FIG. 5F shows another arrangement with four magnets 320, a spacer, andtwo coils 410. Two pairs of magnets 320 are provided on either side ofthe spacer. Two coils 410 are wrapped around the two pairs of magnets320 such that the two coils 410 completely cover the magnets 320 withoutcovering the spacer. The spacer can be a magnetic material ornon-magnetic material.

FIG. 6A illustrates an isometric view of the first elastic member 230A.FIG. 6B and FIG. 6C illustrate a side view and a back view of the firstelastic member 230A. The pair of first elastic members 230 comprises afirst elastic member 230A and a first elastic member 230B. The firstelastic member 230A and the first elastic member 230B are exactlysimilar in shape and size, but can be slightly different to each otherin other variations.

Moving to the construction of the pair of first elastic members 230, thefirst elastic member 230A and the first elastic member 230B comprisefive different sections: a hexagonal base plate 602, a first roundedbend 604, a long strip 606 with indentations 612, which are symmetricalalong the centre of the long strip 606 in the transversal direction(Y-axis), a second rounded bend 608 and a rectangular upper plate 610,to form a “Z” shaped structure with rounded edges.

The hexagonal base plate 602 and the rectangular upper plate 610projecting from the long strip 606 are in opposite directions in thelongitudinal direction (X-axis), such that they are parallel or nearlyparallel. The hexagonal base plate 602 is comparatively larger than therectangular upper plate 610. The hexagonal base plate 602 of the firstelastic member 230A is affixed to the protruding element 164 of thechassis 160. Likewise, the hexagonal base plate 602 of the first elasticmember 230B is affixed to the protruding element 162 of the chassis 160.Similarly, the upper plates 610 of the first elastic member 230A and thefirst elastic member 230B are attached to the frame 310 on diagonallyopposite sides. The first elastic member 230A and the first elasticmember 230B are attached to the frame 310 and the protruding element 162and the protruding element 164 of the chassis 160 such that the upperplates 610 and the hexagonal base plates 602 are diagonally opposite toeach other and act as a spring to restrain the movement of the firstmoving part 210. By varying the material and mass of the frame 310 andthe magnets 320, and elasticity of the first elastic member 230A andfirst elastic member 230B, the first resonant frequency of the vibratingactuator can be controlled, altered or designed. The complete assemblyfor the first elastic member 230A and the first elastic member 230B canbe fabricated by cutting and folding an elastic metal sheet. The metalused for fabrication can include stainless steel, copper beryllium orother elastic metal having high tensile strength. In an alternativeimplementation, the first elastic member 230A and the first elasticmember 230B are made by molding or printing, by a 3D printer, highlydurable, yet elastic polymers such as polyamide (Nylon).

FIG. 7A shows an isometric view of the holding means 240, which are inthe form of a second elastic member 240A and a second elastic member240B. However, in an exemplary embodiment only one elastic member 240Ais illustrated. FIG. 7B and FIG. 7C illustrate the side view and theback view of the second elastic member 240A. The second elastic member240A and the second elastic member 240B are similar in shape, size andconstruction. The holding means 240, which is in the form of the secondelastic member 240A and the second elastic member 240B comprises fiveparts: a rectangular base plate 702, a first rounded bend 704, a longstrip 706, a second rounded bend 708, and a rectangular upper plate 710as shown in FIG. 7A. The long strip 706 has indentations 712, which aresymmetrical along the centre line of the long strip 706 in thetransversal direction (Y-axis). The long strip 706 has orthogonalprojections terminating into the rectangular base plate 702 in thelongitudinal direction (X-axis), through the first rounded bend 704 atone end and into the rectangular upper plate 710 in the longitudinaldirection (X-axis), with a rounded bend 708, at the other end. Therectangular base plate 702 and the rectangular upper plate 710 projectin the opposite direction from the long strip 706 and are parallel ornearly parallel to each other. The rectangular upper plates 710 of thesecond elastic member 240A and the second elastic member 240B areattached at the diagonally opposite ends of the pair of U-shapedstructures 420. The rectangular base plate 702 of the second elasticmember 240A is attached to the protruding element 164 of the chassis160. Likewise, the rectangular base plate 702 of the second elasticmember 240B is attached to the protruding element 162 of the chassis160. The second elastic member 240A and the second elastic member 240Bare fabricated by cutting and folding an elastic metal sheet to form a“Z” shaped structure as shown in FIG. 7A. The metal used for fabricationcan include stainless steel, copper beryllium or other elastic metalhaving high tensile strength. In an alternative implementation, theholding means 240 formed by the second elastic member 240A and thesecond elastic member 240B is made by molding or printing, by a 3Dprinter, highly durable, yet elastic polymers such as polyamide (Nylon).

Referring to FIGS. 7D and 7E another novel aspect of the presentinvention is shown. The holding means 240 formed by the second elasticmember 240A and the second elastic member 240B are made of a metal whichis a good conductor of electrical current. Additionally, the coils 410are joined at one end to the U-shaped structures 420. The coils areenergised by passing current, which requires a conductive path. A novelway to energise the coils 410 is to provide a conductive path throughthe holding means 240, as shown for the second elastic member 240A inFIG. 7D. A first wire 720A is attached to the second elastic member 240Aby soldering, welding or gluing to the rectangular base plate 702. Asecond wire 720B is affixed to the rectangular upper plate 710 bysoldering, welding or gluing to act as a termination point, which issubsequently connected to at least one of the coils 410.

Referring to FIG. 7E, instead of wire, a flexible printed circuit 730 isoverlaid on the second elastic member 240A, which moves along thesurface of the second elastic member 240A before terminating into atleast one of the coils 410 to provide electric current. Although, thewire 720A and the wire 720B or the flexible printed circuit 730 isoverlaid on the second elastic member 240A in an exemplaryimplementation, however, in another implementation the second elasticmember 240B can also be utilised for overlaying the wire 720A and thewire 720B or the flexible printed circuit 730.

As described earlier, the pair of first elastic members 230 and theholding means 240 are required for connecting the first moving part 210and the second moving part 220 to the chassis 160. However, in thisimplementation only a pair of first elastic members 800 is required asshown in FIG. 8D. FIG. 8D shows an isometric view of the vibratingactuator having the first moving part 210 and the second moving part 220with the pair of first elastic members 800. The pair of first elasticmembers 800 includes a first elastic member 800A and a first elasticmember 800B. FIG. 8A illustrates an isometric view of the first elasticmember 800A. FIG. 8B and FIG. 8C provides a side view and a back view ofthe first elastic member 800A.

The first elastic member 800A comprises a base plate 802, a middle strip806, an upper middle plate 810, and holding means 830. The holding means830 comprises two protruding outer strips 804A and 804B, and a pair ofupper plates 808A and 808B. The holding means 830 protrudes from thebase plate 802 in the form of a pair of outer strips, that is, the outerstrip 804A and the outer strip 804B at the outside edges. The protrudingouter strips 804A and 804B project orthogonally from the base plate 802in the transversal direction (Y-axis) with rounded edges 820, having anindentation along the transversal direction (Y-axis) on the outer faces812A and 812B, while the inner faces are straight and parallel to eachother. Furthermore, the protruding outer strips 804A and 804B terminateinto the upper plates 808A and 808B in the longitudinal direction(X-axis). The upper plates 808A and 808B project orthogonally from thetwo protruding outer strips 804A and 804B such that the folds haverounded edges 820. Further, the two protruding outer strips 804A and804B are parallel or nearly parallel to the base plate 802 and the baseplate 802 and the upper plates 808A and 808B point in oppositedirections. In addition, the upper plates 808A and 808B are separate andindependent of each other.

The middle strip 806 lies in between the outer strips 804A and 804B andextends a small distance, such as 2 mm to 3 mm from the base plate 802in the longitudinal direction (X-axis), and then is folded with roundededges 820 to project orthogonally in the transversal direction (Y-axis)from the base plate 802. Finally, the middle strip 806 terminatesorthogonally, in the longitudinal direction (X-axis), into the uppermiddle plate 810, such that the folds at edges 820 are rounded. Insummary, all the folds of the first elastic member 800A have roundededges 820. The base plate 802 and the upper middle plate 810 areprojected in opposite directions and are parallel or nearly parallel.The middle strip 806 has a symmetrical indentation in the transversaldirection (Y-axis) along its centre line. The upper plates 808A and 808Band the middle plate 810 are separated by a small distance, in thetransversal direction (Y-axis), to allow free vibration of the middleplate 810 underneath the upper plates 808A and 808B.

The first elastic member 800A and the first elastic member 800B areidentical in shape, size, and construction. However, in anothervariation the first elastic member 800A and the first elastic member800B can be different from each other in shape, size and construction.The first elastic member 800A and the first elastic member 800B arefabricated by cutting and folding an elastic metal sheet to form twoindependent Z-like shapes as shown in FIG. 8A. The metal used forfabrication can include stainless steel, copper beryllium or otherelastic metal having high tensile strength. In an alternativeimplementation, the first elastic member 800A and the first elasticmember 800B are made by molding or printing, by a 3D printer, highlydurable, yet elastic polymers such as polyamide (Nylon).

FIG. 8D shows an isometric view of the vibrating actuator using twofirst elastic members 800. The base plate 802 of the first elasticmember 800A is attached by welding or gluing to the protruding element162 of the chassis 160; the upper middle plate 810 is connected bywelding or gluing to the frame 310 of the first moving part 210, whilethe upper plates 808A and 808B of the holding means 830 are attached bywelding or gluing to the U-shaped structure 420A of the second movingpart 220. The base plate 802 of the first elastic member 800B isattached by welding or gluing to the protruding element 164 of thechassis 160; the upper middle plate 810 is connected by welding orgluing to the frame 310 of the first moving part 210, while the upperplates 808A and 808B of the holding means 830 are attached by welding orgluing to the U-shaped structure 420B of the second moving part 220.

FIG. 9D illustrates an isometric view of the vibrating actuator with apair of elastic members configured to provide two different vibrationsin another embodiment of the present invention. The vibrating actuatorincludes the first moving part 210, the second moving part 220, and apair of first elastic members 900. The pair of first elastic members 900comprises a first elastic member 900A and a first elastic member 900B.FIG. 9A illustrates an isometric view of the first elastic member 900A.FIG. 9B and FIG. 9C provide a side view and a front view of the firstelastic member 900A.

The first elastic member 900A comprises a centre plate 904, a middlestrip 908 and a holding means 930. The holding means 930 includes anupper plate 910 suspended by a pair of outer protruding flat strips 906Aand 906B, and base plate 902A and the base plate 902B with rounded edges920 at all orthogonal folds.

The base plate 902A and the base plate 902B are preferably rectangularin shape, and are independent. The base plate 902A and the base plate902B protrude orthogonally into two independent flat strips, the flatstrip 906A and the flat strip 906B, in the transversal direction(Y-axis). The fold 920 between the base plate 902A and the flat strip906A is rounded. Likewise, the fold 920 between the base plate 902B andthe flat strip 906B is also rounded. Both the protruding flat strips,that is, the flat strip 906A and the flat strip 906B terminate into theupper plate 910. The flat strip 906A and the flat strip 906B and theupper plate 910 are arranged such that the fold 920 between the flatstrip 906A and 906B and the upper plate 910 is rounded. Further, theflat strip 906A has indentations 912A along the transversal direction(Y-axis) at its outer side and the flat strip 906B has indentations 912Bon its outer side. The inner sides of the flat strips 906A and 906B arestraight and parallel. The upper plate 910 and the pair of base plates902A and 902B point in opposite directions, and are aligned such thatthe upper plate 910 and the pair of base plates 902A and 902B areparallel or nearly parallel to each other.

The middle strip 908 lies in between the flat strip 906A and the flatstrip 906B and projects at an acute angle respective to the upper plate910 to terminate into the centre plate 904. The fold 920 between theupper plate 910 and the middle strip 908 is rounded, likewise therounded fold 920 is provided in between the centre plate 904 and themiddle strip 908. In addition, the centre plate 904 and the upper plate910 point in the same direction and are aligned such that the centreplate 904 and the upper plate 910 are parallel or nearly parallel toeach other. The middle strip 908 has symmetrical indentations in thetransversal direction (Y-axis) along its centre line. The terminationpoints of the middle strip 908 and the flat strips 906A and 906B on theupper plate 910 are collinear.

The first elastic member 900A and the first elastic member 900B areidentical in shape, size, and construction. However, in anothervariation the first elastic member 900A and the first elastic member900B can be different from each other in shape, size and construction.The first elastic member 900A or the first elastic member 900B isfabricated by cutting and folding an elastic metal sheet. The metal usedfor fabrication can include stainless steel, copper beryllium or otherelastic metal having high tensile strength. In an alternativeimplementation, the first elastic member 900A and the first elasticmember 900B are made by molding or printing, by a 3D printer, highlydurable, yet elastic polymers such as polyamide (Nylon).

FIG. 9D shows an isometric view of the vibration actuator using the pairof first elastic members 900. The base plate 902A and the base plate902B of the holding means 930 of the first elastic member 900A areattached to the protruding element 162 by welding or gluing; the upperplate 910 of the holding means 930 is connected by welding or gluing tothe U-shaped structure 420A of the second moving part 220, while thecentre plate 904 is connected by welding or gluing to the frame 310 ofthe first moving part 210. The base plate 902A and the base plate 902Bof the holding means 930 of the first elastic member 900B are attachedto the protruding element 164 by welding or gluing; the upper plate 910of the holding means 930 is connected by welding or gluing to theU-shaped structure 420B of the second moving part 220, while the centreplate 904 is connected by welding or gluing to the frame 310 of thefirst moving part 210.

FIG. 10D shows an isometric view of the vibrating actuator to providetwo different vibrations with a novel pair of another type of elasticmembers in another embodiment of the present invention. The vibratingactuator includes the first moving part 210, the second moving part 220,and a pair of first elastic members 1000. The pair of first elasticmembers 1000 includes a first elastic member 1000A and a first elasticmember 1000B. FIG. 10A illustrates an isometric view of the firstelastic member 1000A. FIG. 10B and FIG. 10C show the side view and theback view of the first elastic member 1000A.

The construction of the first elastic member 1000A is similar to thefirst elastic member 230A and the holding means 240 formed by the secondelastic member 240A; however, the first elastic member 1000A isfabricated by folding a single piece of elastic metal to form a lowerbase plate 1002B, one protruding elastic member 1004, a flat upper plate1008 and a holding means 1030. Referring to FIG. 10A, in an exemplaryembodiment only the first elastic member 1000A of the pair of the firstelastic members 1000 is shown.

Accordingly, the first elastic member 1000A comprises lower base plate1002B, first projected elastic member 1004, flat upper plate 1008 andholding means 1030. The holding means 1030 includes an upper base plate1002A, a second projected elastic member 1006 and a flat upper plate1010. The base plate 1002 protrudes a first projected elastic member1004 and the second projected elastic member 1006 of the holding means1030. The first projected elastic member 1004 is similar to the longstrip 606 of the first elastic member 230A. Likewise, the secondprojected elastic member 1006 is similar to the long strip 706 of thesecond elastic member 240A as discussed earlier.

The holding means 1030, which is formed by the upper base plate 1002Aprotrudes the second projected elastic member 1006 orthogonally alongthe transversal direction (Y-axis). A rounded fold is formed between theupper base plate 1002A and the second projected elastic member 1006. Thesecond projected elastic member 1006 has indentations along thetransversal direction (Y-axis) that are symmetrical along the centreline. The second projected elastic member 1006 terminates orthogonally,with rounded edges, into a flat upper plate 1010. The upper base plate1002A and the flat upper plate 1010 are parallel or nearly parallel andpoint in opposite directions to each other in the longitudinal direction(X-axis).

The lower base plate 1002B extends a small distance, such as 2 mm to 3mm, from the termination point of the upper base plate 1002A beforeprotruding orthogonally in the transversal direction (Y-axis) into thefirst projected elastic member 1004. A rounded fold is formed betweenthe first projected elastic member 1004 and the lower base plate 1002B.The first projected elastic member 1004 has indentations along thetransversal direction (Y-axis) that are symmetrical along its centreline. The first projected elastic member 1004 terminates orthogonallyinto a flat upper plate 1008 such that the fold has rounded edges. Thelower base plate 1002B and the flat upper plate 1008 are parallel ornearly parallel and point in opposite directions to each other in thelongitudinal direction (X-axis). The lower base plate 1002B, firstprojected elastic member 1004, and flat upper plate 1008 form one Z-likestructure. Likewise, the upper base plate 1002A, second projectedelastic member 1006, and flat upper plate 1010 form a second Z-likestructure. The two Z-like structures are independent to each other andhave a distance of a few millimeters between them, for example, 2 mm to4 mm, in the longitudinal direction (X-axis). Further, the flat upperplate 1010 is broader in the axis orthogonal to the X-Y-plane (Z-axis)to the flat upper plate 1008, as shown in FIG. 10C. In addition, theflat upper plate 1010 is 1 mm to 2 mm above the flat upper plate 1008 inthe transversal direction (Y-axis).

The first elastic member 1000A and the first elastic member 1000B areidentical in shape, size, and construction. However, in anothervariation the first elastic member 1000A and the first elastic member1000B can be different from each other in shape, size and construction.The first elastic member 1000A and the first elastic member 1000B arefabricated by cutting and folding an elastic metal sheet. The metal usedfor fabrication can include stainless steel, copper beryllium or otherelastic metal having high tensile strength. In an alternativeimplementation, the first elastic member 1000A and the first elasticmember 1000B are made by molding or printing, by a 3D printer, highlydurable, yet elastic polymers such as polyamide (Nylon).

FIG. 10D shows an isometric view of the vibration actuator using thepair of first elastic members 1000. The base plate 1002 of the firstelastic member 1002A is attached to the protruding element 162 bywelding or gluing; the flat upper plate 1010 of the holding means 1030is connected by welding or gluing to the U-shaped structure 420A of thesecond moving part 220, while the flat upper plate 1008 is connected bywelding or gluing to the frame 310 of the first moving part 210. Thebase plate 1002 of the first elastic member 1002B is attached to theprotruding element 164 by welding or gluing; the flat upper plates 1010of the holding means 1030 is connected by welding or gluing to theU-shaped structure 420B of the second moving part 220, while the flatupper plate 1008 is connected by welding or gluing to the frame 310 ofthe first moving part 210.

FIG. 11A shows another implementation of the vibrating actuator 1100using a different type of elastic members. In this implementation, thechassis 160 has a protruding element 1130 and a protruding element 1140,which are rectangular in structure, as shown in FIG. 11A.

The vibrating actuator 1100 comprises the first moving part 210, thesecond moving part 220, a pair of first elastic members 1110, and aholding means 1120 formed by a pair of second elastic members, that is,a second elastic member 1120A and a second elastic member 1120B. Thepair of first elastic members 1110 comprises a first elastic member1110A and a first elastic member 1110B. The first moving part 210comprises the frame 310, the magnets 320 and the second moving partcomprises the U-shaped structures 420 and the coils 410, arranged suchthat the first moving part 210 moves freely in the hollow tubularstructure of the second moving part 220. The construction andconfiguration of the first moving part 210 and the second moving part220 have been described earlier.

The first elastic member 1110A and the first elastic member 1110B areT-shaped flat metal strips. In addition, the first elastic member 1110Aand the first elastic member 1110B have indentations along thetransversal direction (Y-axis) that are symmetrical along their centrelines in the long portion of the T-shape. The second elastic member1120A and the second elastic member 1120B are flat long metal stripsacting as the holding means 1120. In addition, the second elastic member1120A and the second elastic member 1120B have indentations along thetransversal direction (Y-axis) that are symmetrical along their centrelines.

The first elastic member 1110A, the first elastic member 1110B, thesecond elastic member 1120A and the second elastic member 1120B arefabricated by cutting an elastic metal sheet. The metal used forfabrication can include stainless steel, copper beryllium or otherelastic metal having high tensile strength. In an alternativeimplementation, the first elastic member 1110A, the first elastic member1110B, the second elastic member 1120A and the second elastic member1120B are made by molding or printing, by a 3D printer, highly durable,yet elastic polymers such as polyamide (Nylon).

FIG. 11B shows an isometric view of the vibration actuator 1100 usingthe pair of first elastic members 1110 and the holding means 1120. Thenarrow end of the T-shaped first elastic member 1110A and the firstelastic member 1110B are affixed to the frame 310 of the first movingpart 210 by welding, gluing, or riveting on diagonally opposite corners.The broad end of the T-shaped first elastic member 1110A is affixed tothe rectangular protruding element 1140, on its inner side, that is theside which faces the other rectangular protruding element 1130 in thelongitudinal direction (X-axis). Similarly, the broad end of theT-shaped first elastic member 1110B is affixed to the rectangularprotruding element 1130 on its inner side, that is the side which facesthe other rectangular protruding element 1140 in the longitudinaldirection (X-axis). The T-shaped first elastic member 1110A and therectangular protruding element 1140, and the T-shaped first elasticmember 1110B and the rectangular protruding element 1130 are affixed bywelding, gluing or riveting.

The outer protruding surface 1150A of the U-shaped structure 420A is inthe transversal direction (Y-axis) and is utilised for affixing thesecond elastic member 1120A. Likewise, the outer protruding surface1150B of the U-shaped structure 420B is in the transversal direction(Y-axis) and is utilised for affixing the second elastic member 1120B.The second elastic member 1120A and the outer protruding surface 1150A,and the second elastic member 1120B and the outer protruding surface1150B are affixed by welding, gluing or riveting. The joints made by thesecond elastic member 1120A and the second elastic member 1120B and theouter protruding surface 1150A and 1150B are diagonally opposite to eachother.

The opposite end of the second elastic member 1120A is affixed to therectangular protruding element 1140 on its outer side, that is the sidewhich faces outwards in the longitudinal direction (X-axis) towards theend of the chassis 160. Similarly, the opposite end of the secondelastic member 1120B, is affixed to the outer side of the rectangularprotruding element 1130. The second elastic member 1120A and therectangular protruding element 1140, and the second elastic member 1120Band the solid rectangular protruding element 1130 are affixed bywelding, gluing or riveting.

FIG. 12A shows another variation of the vibrating actuator 1200 with apair of first elastic members 1110 and a holding means 1120 formed by apair of second elastic members, that is, an elastic member 1120A and anelastic member 1120B having holes for affixing to the chassis 160. Thepair of first elastic members 1110 includes an elastic member 1110A andan elastic member 1110B. The elastic member 1110A and the elastic member1110B are identical to each other. Similarly, the elastic member 1120Aand the elastic member 1120B are identical to each other.

The vibrating actuator 1200 comprises the first moving part 210 and thesecond moving part 220, the pair of first elastic members 1110, and thepair of second elastic members 1120. The first elastic member 1110A andthe first elastic member 1110B, which are T-shaped as described earlier,have three holes 1208 punched in the broad end and one hole 1208 punchedin the narrow end. The broad end has a hole 1208 at the T-joint and onehole on each other side. The opposite narrow end has a hole 1208, whichis collinear to the hole 1208 on the T-joint of the broad end.

A pair of threaded holes 1206A and 1206B are provided in the frame 310of the first moving part 210. The threaded holes 1206A and 1206B areprovided on diagonally opposite corners of the frame 310, such that thepair of first elastic members 1110 can be affixed onto the frame 310using screws 1202.

In this variation, the protruding element 162 and the protruding element164 associated with the chassis 160 have an extruded “P” shape and havethreaded holes 1204A and 1204B on their inner face. The threaded hole1204A and the threaded hole 1204B face each other and are diagonallyopposite in the longitudinal direction (X-axis). In addition, the innerface of the P-shaped protruding element 164 also has at least twoplastic or metal extrusions 1214A on either side of the threaded hole1204A that are orthogonal to the X-Y-plane (Z-axis). Likewise, the innerface of the P-shaped protruding element 162 has at least two plastic ormetal extrusions 1214B on either side of the threaded hole 1204B thatare orthogonal to the X-Y-plane (Z-axis). The outer face of the P-shapedprotruding element 164, that is the face which is directed outwards inthe longitudinal direction (X-axis) towards the end of the chassis 160,has two threaded holes 1212A towards its outer edges in the axisorthogonal to the X-Y-plane (Z-axis). Likewise, the outer face of theP-shaped protruding element 162 has two threaded holes 1212B towards itsouter edges in the axis orthogonal to the X-Y-plane (Z-axis), as shownin FIG. 12A.

As discussed earlier, the first elastic member 1110A has three holes onthe broad end. The middle hole 1208 on the T-joint is utilised forattaching the first elastic member 1110A to the inner side of theP-shaped protruding element 164 by fastening a screw 1202 into thethreaded hole 1204A. In addition, the extrusions 1214A on either side ofthe threaded hole 1204A mate perfectly with the two outer holes 1208 onthe broad side of the first elastic member 1110A to secure it with theP-shaped protruding element 164. Likewise, the first elastic member1110B has three holes on the broad end. The middle hole 1208 on theT-joint is utilised for attaching the first elastic member 1110B to theinner side of the P-shaped protruding element 162 by fastening a screw1202 into the threaded hole 1204B. In addition, the extrusions 1214B oneither side of the threaded hole 1204B mate perfectly with the two outerholes 1208 on the broad side of the first elastic member 1110B to secureit with the P-shaped protruding element 162.

The holding means 1120 formed by the second elastic member 1120A and thesecond elastic member 1120B, which are long metal strips as describedearlier, have four holes 1210 punched at the four corners. One end ofthe second elastic member 1120A, having two holes 1210, is fastened byusing two screws 1202, into the threaded receiving holes 1222A on theouter face of the U-shaped structure 420A. The opposite end of thesecond elastic member 1120A, having two holes 1210, is fastened usingtwo screws 1202, into the threaded receiving holes 1212A on the outerface of the P-shaped protruding element 164. Likewise, the one end ofthe second elastic member 1120B, having two holes 1210, is fastened byusing two screws 1202, into the threaded receiving holes 1222B, on theouter face of the U-shaped structure 420B. The opposite end of thesecond elastic member 1120B, having two holes 1210, is fastened by usingtwo screws 1202, into the two threaded receiving holes 1212B on theouter face of the P-shaped protruding element 162. Finally, theassembled vibrating actuator 1200 is produced.

FIG. 12B shows an isometric view of the vibrating actuator 1200assembled using the screws 1202 for affixing the first elastic members1110 with punched holes and the holding means 1120 with punched holes inthis implemented variation of the invention.

FIG. 13A and FIG. 13B show the arrangement of the first moving part 210relative to the second moving part 220. When the coils 410 are energisedby an alternating electric current, the alternating current interactswith the permanent magnetic field of the magnets 320 to produce twoopposing forces according to the Lorentz Force principle. Initially, atrest, the two opposing forces move the first moving part 210 and thesecond moving part 220 in opposite directions. When the alternatingcurrent is reversed in the coils 410, the alternating current interactswith the permanent magnetic field of the magnets 320 to produce twoopposing forces in the reverse direction. The first moving part 210 isconstrained by the pair of first elastic members 230 and produces arecoil due to elasticity. When the recoil energy stored in the pair offirst elastic members 230 is released, it aids the movement of the firstmoving part 210 thereby producing vibratory motion. Similarly, thesecond moving part 220 is constrained by the holding means 240 formed bythe pair of second elastic members (second elastic member 240A andsecond elastic member 240B) and produces a recoil due to elasticity.When the recoil energy stored in holding means 240 is released it aidsthe movement of the second moving part 220 thereby also producingvibratory motion.

The vibration frequency of the first moving part 210 depends upon atleast the mass of the frame 310, the mass of the magnets 320, and theelastic constant of the pair of first elastic members 230. Likewise, thevibration frequency of the second moving part 220 depends upon at leastthe mass of the U-shaped structures 420, the mass of the coils 410, andthe elastic constant of holding means 240. Finally, the first movingpart 210 produces a linear oscillatory movement in the longitudinaldirection (X-axis) with resonant frequency F1 and the second moving part220 produces a linear oscillatory movement in the longitudinal direction(X-axis) with resonant frequency F2. The first resonant frequency F1 andthe second resonant frequency F2 are different and far apart. Forexample, the first resonant frequency F1 can be 40 Hz and the secondresonant frequency F2 can be 75 Hz.

FIG. 14A shows the cross sectional view of the vibrating actuator alongthe transversal (Y-axis) at its centre plane and FIG. 14B shows thecross sectional view of the vibrating actuator along the longitudinal(X-axis) at its centre plane.

A directed magnetic field is generated by the magnets 320 embeddedinside the frame 310 with like poles facing each other. The magneticfield flows radially outwards (for example, outwards transversally(Y-axis)) from the magnets 320, at the intersection point of magnets320, where the north poles of the magnets 320 face each other, andtransverses the coils 410. Furthermore, the magnetic field flows inwards(for example, inward transversally (Y-axis)), transverses the coils 410and into the magnets 320, at the intersection point of magnets 320,where south poles of the magnets 320 face each other. When the coils 410are energized by passing the alternating current in the presence of thedirected magnetic field, a force is produced on the second moving part220 according to the Lorentz Force principle; accordingly, the firstmoving part 210 experiences a force in the opposite direction. Further,the two coils 410 are wound in opposite directions, so that when thecurrent flows through the coils 410, the second moving part 220experiences a force unilaterally in one direction. When the alternatingcurrent is reversed, the second moving part 220 experiences a force inthe opposite direction. This phenomenon creates vibratory motion in thesecond moving part 220. Likewise, the first moving part 210 alsoexperiences a force according to the Lorentz Force principle thatproduces a second vibratory motion independent of the first vibratorymotion. The motion of the first moving part 210 is relative to thesecond moving part 220 and can be in the same direction or in theopposite direction.

Disclosed is a vibrating actuator having two different frequencies ofvibration. The vibrating actuator 100 comprises the first moving part210 including at least three magnets 320. The three magnets 320 arearranged with like polarities facing each other. Further, the vibratingactuator includes the second moving part 220, which includes at leasttwo coils 410. The coils 410 are wound over the magnets 320 such thatthe magnetic field of the magnets 320 perpendicularly transverses thecoils 410. The pair of first elastic members (230; 800; 900; 1000; 1120)are attached to the first moving part 210 at one end and to the chassis160 at the other end. A holding means (240; 830; 930; 1030; 1120)connects the second moving part 220 to the chassis 160 such that theholding means (240; 830; 930; 1030; 1120) are a pair of elastic members(240; 1120) or form part of the first elastic members (800; 900; 1000).In one implementation, the holding means are the pair of elastic members(240; 1120), for example, the holding means are the second elasticmember (240A; 1120A) and the second elastic member (240B; 1120B). In analternate implementation, the holding means 1030 form part of the pairof first elastic members 1000 such that each first elastic member(1000A, 1000B) has at least one holding means 1030. For example, theholding means 1030 is located in front of the first projected elasticmember 1004 of the first elastic member 1000A and the first elasticmember 1000B. In yet another alternate implementation, the holding means(830; 930) form part of the pair of first elastic members (800; 900)such that each first elastic member (800A, 800B; 900A, 900B) has morethan one holding means (830; 930). In one example, the holding means 830are located on either side of the middle strip 806 of the first elasticmember 800A or the first elastic member 800B. In another example, theholding means 930 are located on either side of the middle strip 908 ofthe first elastic member 900A or the first elastic member 900B. Otherimplementations and variations such as using plastic, rubber, or otherelastic material for fabricating the holding means (240; 830; 930; 1030;1120) are also possible.

The holding means 240 are attached to the chassis 160 at one end and tothe second moving part 220 at the other end. In one variation, theholding means 830 are attached to the chassis 160 at one end and to thesecond moving part 220 at the other end. In another variation of thisimplementation, the holding means 930 are attached at the second movingpart 220 at one end and the other end is attached to chassis 160. In yetanother variation, the holding means 1030 are attached to the chassis160 at one end and to the second moving part 220 at the other end.

In one implementation, the vibrating actuator includes a pair of thefirst elastic members 800. Each first elastic member 800A and firstelastic member 800B is formed from a base plate 802 having the holdingmeans 830. The holding means 830 comprises the outer strip 804A and theouter strip 804B. The outer strip 804A and the outer strip 804B havetransversal indentations on the outer faces (812A and 812B), and areprojected orthogonally at equal distance from the base plate 802 toterminate into the upper plate 808A and the upper plate 808B. The upperplate 808A and 808B are utilised as attachment means for the secondmoving part 220. The holding means 830 allow free suspension of thesecond moving part 220.

In another implementation, the vibrating actuator includes a pair of thefirst elastic members 900. The first elastic member 900A and the firstelastic member 900B comprises a holding means 930, which includes anupper plate 910; the upper plate 910 has at least two orthogonalindependent protruding flat strips 906A and 906B having rounded edges920. The outer two protruding flat strips 906A and 906B terminate intobase plates 902A and 902B, which are parallel to the upper plate 910 andare projected into opposite directions with respect to the upper plate910. One end of the holding means 930 is attached to chassis 160 withthe base plates 902A and 902B, while the other end is affixed to thesecond moving part 220. The holding means 930 allow free suspension ofthe second moving part 220.

In one embodiment, the vibrating actuator has the holding means (240;830; 930; 1030; 1120), which has a provision of carrying electricalcurrent to the coils (410) by an overlaid conductive path. In anotherimplementation of the present invention, the overlaid conductive path onthe holding means (240; 830; 930; 1030; 1120) is a flexible printedcircuit or is a wire for providing current to the coils (410). The wirecan be insulated from the pair of elastic members (230; 800; 900; 1000,1110).

In yet another implementation, the holding means (240; 830; 930; 1030;1120) can itself act as a conducting path to provide current to thecolis 410.

In one implementation of the present invention, the pair of firstelastic members (230; 800; 900; 1000, 1110) are perforated.

In another implementation of the present invention, the holding means(240; 830; 930; 1030; 1120) are perforated.

In yet another implementation, both the first elastic members (230; 800;900; 1000, 1110) and the holding means (240; 830; 930; 1030; 1120) areperforated

The vibrating actuators described herein are exemplary only. Otherconfigurations and variations provided herein are non-limiting and anymodifications fall well within the scope of this invention. Thefunctionality and use of the vibrating actuator are for illustrativepurposes and are not intended to be limiting in any manner. Furthermore,the different components of the vibrating actuator can be suitablymodified to provide additional functionality.

1. A vibrating actuator having two different frequencies of vibration,the vibrating actuator comprising: a first moving part (210) includingat least three magnets (320), wherein the magnets (320) are arrangedwith like polarities facing each other; a second moving part (220)including at least two coils (410), wherein the coils (410) are woundover the magnets (320); and a pair of first elastic members (230; 800;1000; 1110) affixed to a chassis (160) and to the first moving part(210); and holding means (240; 830; 1030; 1120) which are affixed to thesecond moving part (220) and which furthermore either are affixed to thechassis (160) or form part of the pair of first elastic members (230;800; 1000).
 2. The vibrating actuator according to claim 1, wherein thepair of first elastic members (230) is affixed to the chassis (160) atone end and to the first moving part (210) at the other end; and whereinthe holding means (240) are a pair of second elastic members affixed tothe chassis (160) at one end and the second moving part (220) at theother end.
 3. The vibrating actuator of claim 1, wherein the pair offirst elastic members (230; 800; 1000; 1110) produce a first vibrationfrequency and the holding means (240; 830; 1030; 1120) produce a secondvibration frequency, wherein the first vibration frequency is differentthan the second vibration frequency and the first moving part (210) andthe second moving part (220) vibrate along the longitudinal axis inopposite directions.
 4. The vibrating actuator of claim 1, wherein thechassis (160) has protruding elements (162, 164) at diagonally oppositeends along the longitudinal axis having means to attach the pair offirst elastic members (230; 800; 1000; 1110) and the holding means (240;830; 1030; 1120) either by welding or affixing with screws.
 5. Thevibrating actuator of claim 1, wherein the holding means (240; 830;1030; 1120) has a provision for carrying current to the coils (410) byoverlaying a conductive path on at least one elastic member (240A,240B), wherein the overlaid path is made of a flexible printed circuitor a wire.
 6. The vibrating actuator of claim 1, wherein the holdingmeans (240; 830; 1030; 1120) has a provision for carrying current to thecoils (410) by acting as a conductive path.
 7. The vibrating actuator ofclaim 1, wherein the first moving part (210) comprises a frame (310) andthe magnets (320) and wherein the magnets (322, 324, 326) have equaltransverse width and at least two magnets (322, 326) have equallongitudinal length.
 8. The vibrating actuator of claim 7, wherein themagnets (322, 324, 326) have a spacer made of nonmagnetic materialembedded at the intersection of the magnets (320).
 9. The vibratingactuator of claim 7, wherein the frame (310) is a square or rectangleand is made of a non-ferromagnetic material.
 10. The vibrating actuatorof claim 1, wherein the first moving part (210) comprises a frame (310)and wherein the coils (410) are wrapped transversally around a frame(310) to form a longitudinal tubular structure to allow free movement ofthe coils (410) over the frame (310).
 11. The vibrating actuator ofclaim 1, wherein the coils (410), which are a pair of coils (412, 414),are attached to each other such that the coils (412, 414) carry currentand are wound in opposite directions.
 12. The vibrating actuator ofclaim 11, further comprising a pair of U-shaped structures (420),wherein each U-shaped structure (420A, 420B) is attached to the coils(412, 414) such that the U-shaped structures (420A, 420B) are alignedopposite to each other.
 13. The vibrating actuator of claim 12, whereinthe U-shaped structures (420) and the coils (410) are connected to forma hollow tubular structure that slides over a frame (310) to allow freemovement of the second moving part (220) and the first moving part (210)and wherein the number of coils (410) is one less than the number ofmagnets (320).
 14. The vibrating actuator of claim 12, wherein theU-shaped structures (420) are closed at the open face to form a tubularstructure.
 15. The vibrating actuator of claim 1, wherein the pair offirst elastic members (230) are made of stainless steel having a Z likeshape with two flat protruding elements (602, 610) in oppositedirections.
 16. The vibrating actuator of claim 1, wherein the pair offirst elastic members (230; 800; 1000; 1110) are perforated.
 17. Thevibrating actuator of claim 15, wherein the pair of first elasticmembers (230) are a long strip (606) connecting the two flat protrudingelements (602, 610), which are parallel to each other, folded at 90degrees with rounded edges, and wherein one of the protruding elements(602) is substantially larger than the other protruding element (610)and the flat strip connecting the protruding elements (602, 610) hastraversal indentations symmetrical along the centre of the long strip(606).
 18. The vibrating actuator of claim 2, wherein the holding means(240) comprising the pair of second elastic members are broader alongthe Z-axis than the pair of first elastic members (230) and are made ofstainless steel with a Z like shape having two flat protruding elements(702, 710) projecting in opposite directions.
 19. The vibrating actuatorof claim 18, wherein the holding means (240) includes a long strip (706)connecting the two flat protruding elements (702, 710) and hastransversal indentations symmetrical along the centre of the long strip(706).
 20. The vibrating actuator of claim 1, wherein the holding means(240; 830; 1030; 1120) are perforated.
 21. The vibrating actuatoraccording to claim 1, wherein each of the pair of first elastic members(800) comprises a base plate (802) which is affixed to the chassis (160)and a middle strip (806) which projects from the base plate (802) andwhich is affixed to the first moving part (210); and wherein the holdingmeans (830) comprise a pair of outer strips (804A, 804B), which projectfrom the base plate (802) and which are affixed to the second movingpart (220).
 22. The vibrating actuator according to claim 1, whereineach of the pair of first elastic members (1000) comprises: a base plate(1002) which is affixed to the chassis (160) and a first elastic member(1004) which projects from the base plate (1002) and which is affixed tothe first moving part (210); and wherein the holding means (1030)comprise a second elastic member (1006), which projects from the baseplate (1002) and which is affixed to the second moving part (220).
 23. Amethod for manufacturing a vibrating actuator, comprising the followingsteps: assembling a first moving part (210) by assembling at least threemagnets (322, 324, 326) in a rectangular frame (310), wherein themagnets (320) with like polarities face each other; assembling a secondmoving part (220) by wrapping at least two coils (412, 414) ofself-bonding copper wire around the rectangular frame (310), wherein theat least two coils (412, 414) are attached to a U-shaped structures(420) such that the first ends of the coils (410) are attached to eachother and the second ends of the coils are attached to the U-shapedstructures (420), wherein the U-shaped structures (420) are arrangeddiagonally opposite to each other; attaching a pair of first elasticmembers (230; 800; 1000, 1110) to the first moving part (210); andattaching a holding means (240; 830; 1030; 1120) to the second movingpart (220).